1. Field of the Invention
The present invention relates to a control lever device for a work vehicle comprising a control lever projecting from an opening, and a dust-proof member provided in a position to close the lever-extending opening to be movable along with the control lever.
2. Description of the Related Art
The control lever device as noted above is well known. For example, Japanese Unexamined Patent Application Publication No. 9-86209 discloses a control lever device comprising a shift lever acting as a control lever, a housing including a linear guide groove formed therein for receiving the shift lever, and a flexible slide cover mounted under the guide groove to be movable in unison with the shift lever. Further, a guide rail is mounted for slidably supporting the slide cover at a position in the proximity of the bottom surface of the housing around the guide groove.
A dust-proof arrangement disclosed in the above Japanese reference is applied to a shift lever device for shifting an automatic change-speed device of an automobile. On the top surface of the housing are printed letters such as “P” or “L” indicating shifting positions. The shift lever extends through the slide cover, and the slide cover, in turn, follows movement of the shift lever when operated to close the guide groove. This prevents entry of foreign matters into the guide groove from the outside.
On the other hand, such a control lever device cannot be applied, as it stands, to a work vehicle such as a tractor that includes numerous control levers mounted on a drivers section. In such a work vehicle, a plurality of control levers are adjacent to each other and movable along moving paths arranged in parallel with each other. Further, since each control lever is operated independently, applying the conventional dust-proof arrangement for a single shift lever to such a work vehicle results in a complicated construction and hampers smooth operations of the levers. In addition, numerous parts are required, which eventually increases the cost. In particular, the work vehicle including the tractor comprises a cabin for improving a working environment, and thus has to reliably prevent dust and dirt from entering the interior of the cabin through guide grooves for the control levers.